Microproteinuria in patients with inflammatory bowel disease:Is it associated with the disease activity or the treatment with 5-aminosalicylic acid?

AIM： To investigate whether microproteinuria in patients with inflammatory bowel disease （IBD） is associated with the disease activity or the treatment with 5-aminosalicylic acid （5-ASA）. METHODS： We prospectively studied microproteinuria in 86 consecutive patients with IBD, 61 with ulcerative colitis （UC） and 25 with Crohn＇s disease （CD）, before as well as 2 and 6 months after their inclusion in the study. Forty-six patients received 5-ASA for a period of 28.8 months （range 1-168 too）. Microalbuminuria （mALB） and urine levels of the renal tubular proteins β2-microglobulin （β2mGLB） and β-N-acetyI-D-glucosamidase （β-NAG） as well as the creatinine clearance were determined in a 12-h overnight urine collection. Tumor necrosis factor-α （TNF-α） serum levels were also measured. RESULTS： A total of 277 measurements （194 in UC patients and 83 in CD patients） were performed. The prevalence of abnormal microoproteinuria in UC and CD patients was 12.9% and 6.0% for mALB, 22.7% and 27.7% for B2mGLB, and 11.3% and 8.4% for β-NAG, respectively, mALB was not associated with IBD activity. β2mGLB and B-NAG urine levels were correlated to UC activity （UCAI： P〈0.01; UCEI： P〈0.005）. mALB in UC patients and β-NAG urine levels in CD patients were related to TNF-α serum levels. An association was noticed between microproteinuria and smoking habit. Treatment with 5-ASA was not correlated to the severity of microproteinuria or to the changes of creatinine clearance.CONCLUSION： Microproteinuria is mainly associated with UC and its activity but not affected by 5-ASA.

5-aminosalicylicacid is an attractive candidate agent for chemoprevention of colon cancer in patients with inflammatory bowel disease

Inflammatory bowel disease (IBD) is classically subdivided into ulcerative colitis (UC) and Crohn's disease (CD). Patients with IBD have increased risk for colorectal cancer. Because the pathogenesis of colorectal carcinoma has not been entirely defined yet and there is no ideal treatment for colon cancer, cancer prevention has become increasingly important in patients with IBD. The two adopted methods to prevent the development of colon cancer in clinical practice include the prophylactic colectomy and colonoscopic surveillance.But patients and physicians seldom accept colectomy as a routine preventive method and most patients do not undergo appropriate colonoscopic surveillance. Chemoprevention refers to the use of natural or synthetic chemical agents to reverse, suppress, or to delay the process of carcinogenesis.Chemoprevention is a particularly useful method in the management of patients at high risk for the development of specific cancers based on inborn genetic susceptibility, the presence of cancer-associated disease, or other known risk factors. Prevention of colorectal cancer by administration of chemopreventive agents is one of the most promising options for IBD patients who are at increased risks of the disease. The chemopreventive efficacy of nonsteroidal antiinflammatory drugs (NSAIDs) against intestinal tumors has been well established. But with reports that NSAIDs aggravated the symptoms of colitis, their sustained use for the purpose of cancer chemoprevention has been relatively contraindicated in IBD patients. Another hopeful candidate chemoprevention drug for IBD patients is 5-aminosalicylic acid (5-ASA), which is well tolerated by most patients and has limited systemic adverse effects, and no gastrointestinal toxicity. 5-ASA lacks the well-known side effects of longterm NSAIDs use. Retrospective correlative studies have suggested that the long-term use of 5-ASA in IBD patients may significantly reduce the risk of development of colorectal cancer. According to the literature, this agent might well satisfy clinical expectations with respect to a safe and effective chemopreventive agent.

Severe chest pain in a pediatric ulcerative colitis patient after 5-aminosalicylic acid therapy

Severe reactions to mesalamine products are rarely seen in pediatric patients. We report a case of a 12-year-old boy who had a severe cardiac reaction to a mesalamine product Asacol. Past medical history is significant for ulcerative colitis (UC) diagnosed at 9 years of age. Colo- noscopy one week prior to admission revealed pancoli- tis. He was treated with Asacol 800 mg three times per day and prednisone 20 mg/d. He was subsequently ad- mitted to the hospital for an exacerbation of his UC and started on intravenous solumedrol. He had improvement of his abdominal pain and diarrhea. The patient com- plained of new onset of chest pain upon initiating Asacol therapy. Electrocardiogram (ECG) revealed non-specific ST-T wave changes with T-wave inversion in the lateral leads. Echocardiogram (ECHO) revealed low-normal to mildly depressed left ventricular systolic function. The left main coronary artery and left anterior descending artery were mildly prominent measuring 5 mm and 4.7 mm, respectively. His chest pain completely resolved within 24-36 h of discontinuing Asacol. A repeat echo- cardiogram performed two days later revealed normal left ventricular function with normal coronary arteries (< 3.5 mm). Onset of chest pain after Asacol and im- mediate improvement of chest pain, as well as improve- ment of echocardiogram and ECG findings after discon- tinuing Asacol suggests that our patient suffered from a rare drug-hypersensitivity reaction to Asacol.

Epstein-Barr virus is related with 5-aminosalicylic acid, tonsillectomy, and CD19^+ cells in Crohn's disease

AIM: To study anti-Epstein-Barr virus(EBV) Ig G antibodies in Crohn′s disease in relation to treatment, immune cells, and prior tonsillectomy/appendectomy.METHODS: This study included 36 CD patients and 36 healthy individuals(controls), and evaluated different clinical scenarios(new patient, remission and active disease), previous mucosa-associated lymphoid tissue removal(tonsillectomy and appendectomy) and therapeutic regimens(5-aminosalicylic acid, azathioprine, anti-tumor necrosis factor, antibiotics, and corticosteroids). T and B cells subsets in peripheral blood were analyzed by flow cytometry(markers included: CD45, CD4, CD8, CD3, CD19, CD56, CD2, CD3, TCRαβ and TCRγδ) to relate with the levels of anti-EBV Ig G antibodies, determined by enzyme-linked immunosorbent assay.RESULTS: The lowest anti-EBV Ig G levels were observed in the group of patients that were not in a specific treatment(95.4 ± 53.9 U/m L vs 131.5 ± 46.2 U/m L, P = 0.038). The patients that were treated with 5-aminosalicylic acid showed the highest anti-EBV Ig G values(144.3 U/m L vs 102.6 U/m L, P = 0.045). CD19+ cells had the largest decrease in the group of CD patients that received treatment(138.6 vs 223.9; P = 0.022). The analysis of anti-EBV Ig G with respect to the presence or absence of tonsillectomy showed the highest values in the tonsillectomy group of CD patients(169.2 ± 20.7 U/m L vs 106.1 ± 50.3 U/m L, P = 0.002). However, in the group of healthy controls, no differences were seen between those who had been tonsillectomized and subjects who had not been operated on(134.0 ± 52.5 U/m L vs 127.7 ± 48.1 U/m L, P = 0.523).CONCLUSION: High anti-EBV Ig G levels in CD are associated with 5-aminosalicylic acid treatment, tonsillectomy, and decrease of CD19+ cells.

5-aminosalicylic acid in combination with nimesulide inhibits proliferation of colon carcinoma cells in vitro

AIM: To investigate the effects of 5-aminosalicylic acid (5-ASA) in combination with nimesulide on the proliferation of HT-29 colon carcinoma cells and its potential mechanisms. METHODS: Inhibitory effects of drugs (5-ASA,nimesulide and their combination) on HT-29 colon carcinoma cells were investigated by thiazolyl blue tetrazolium bromide (MTT) assay. Cellular apoptosis and proliferation were detected by TUNEL assay and immunocytochemical staining,respectively. RESULTS: Pretreatment with 5-ASA or nimesulide at the concentration of 10-1000 μmol/L inhibited proliferation of HT-29 colon carcinoma cells in a dose-dependent manner in vitro (t = 5.122,P < 0.05; t = 3.086,P < 0.05,respectively). The inhibition rate of HT-29 colon carcinoma cell proliferation was also increased when pretreated with 5-ASA (100 μmol/L) or nimesulide (100 μmol/L) for 12-96 h,which showed an obvious time-effect relationship (t = 6.149,P < 0.05; t = 4.159,P < 0.05,respectively). At the concentration of 10-500 μmol/L,the apoptotic rate of HT-29 colon carcinoma cells significantly increased (t = 18.156,P < 0.001; t = 19.983,P < 0.001,respectively),while expression of proliferating cell nuclear antigen (PCNA) was remarkably decreased (t = 6.828,P < 0.05; t = 14.024,P < 0.05,respectively). 5-ASA in combination with nimesulide suppressed the proliferation of HT-29 colon carcinoma cells more than either of these agents in a dose-dependent and time-dependent manner (t = 5.448,P < 0.05; t = 4.428,P < 0.05,respectively). CONCLUSION: 5-ASA and nimesulide may inhibit the proliferation of HT-29 colon carcinoma cells and coadministration of these agents may have additional chemopreventive potential.

Duration of treatment with 5-aminosalicylic acid compounds

The development of 5-aminosalicylic acid (5-ASA) therapy as a life long treatment for ulcerative colitis is reviewed from its origins in the 1940s to the present day. The drug was designed to treat rheumatoid arthritis,but was found helpful in the management of nine patients with ulcerative colitis. This discovery preceded the emergence of the clinical trial as a tool for assessing a new drug's efficacy; as a result it lacked scientific rigour and was selective in its presentation of results. Nevertheless it identified the future cornerstone of therapy in ulcerative colitis. In 1962,the first double blind controlled trial of sulphasalazine was conducted on 40 patients. Outcome measures were subjective and included symptoms and an assessment of the rectal mucosa. In 1973,the first two papers on the role of sulphasalazine in maintenance of remission were published. Both used placebo controls and had a stratified design. Outcomes were measured using "an intention to treat" approach. The British study of 64 patients used both subjective and objective criteria to assess outcomes. Patients on placebo had a relapse rate four times patients on active treatment and this founded the basis for a life long approach to therapy with 5-ASA compounds in ulcerative colitis. However,in 1985,a small "on demand" study of 32 patients suggested this approach might be as effective as continuous treatment. Some support for this view came from an Italian study which showed no benefit to continued treatment for those in remission for two years or more. The central problem these studies identify is that of adherence to treatment in the long-term. Few studies have considered patients' attitudes to continuous therapy and it is an area that needs further investigation.

Colon-specific drug delivery systems based on cyclodextrin prod rugs: In vivo evaluation of 5-aminosalicylic acid from its cyclodextrin conjugates

AIM： To investigate the release of cyclodextrin-S-amino- salicylic acid （CyD-S-ASA） in cecum and colon. METHODS： An anti-inflammatory drug 5-ASA was conjugated onto the hydroxyl groups of α-, β- and γ-cydodextrins （CyDs） through an ester linkage, and the in vivo drug release behavior of these prodrugs in rat＇ s gastrointestinal tract after the oral administration was investigated. RESULTS： The 5-ASA concentration in the rat＇s stomach and small intestine after the oral administration of CyD- 5-ASA conjugate was much lower than that after the oral administration of 5-ASA alone. The lower concentration was attributable to the passage of the conjugate through the stomach and small intestine without significant degradation or absorption, followed by the degradation of the conjugate site-specific in the cecum and colon. The oral administration of CyD-S-ASA resulted in lower plasma and urine concentration of 5-ASA than that of 5-ASA alone. CONCLUSION： CyD-5-ASA conjugates may be used as prodrugs for colon-specific drug delivery system.

Can 5-aminosalicylic acid suppository decrease the pain after rectal band ligation?

AIM: To investigate the effect of 5-aminosalicylic acid (5-ASA) suppositories on rectal band ligation-induced pain. METHODS: Sixty patients were randomized into two treatment groups. RESULTS: Our results showed that there was no difference between 5-ASA suppository group and the control group for pain control. CONCLUSION: 5-ASA may be an alternative treatment for hemorrhoids; however, it does not affect the rectal band ligation-induced pain.

Efficacy of Topical versus Oral 5-Aminosalicylate for Treatment of 2,4,6-Trinitrobenzene Sulfonic Acid-induced Ulcerative Colitis in Rats

5-aminosalicylic acid（5-ASA） is drug of choice for the treatment of ulcerative colitis（UC）. In this study, the efficacy of topical versus oral 5-ASA for the treatment of UC was examined as well as the action mechanism of this medication. A flexible tube was inserted into the rat cecum to establish a topical administration model of 2,4,6-trinitrobenzene sulfonic acid（TNBS）-induced UC. A total of 60 rats were divided into sham operation group（receiving an enema of 0.9% saline solution instead of the TNBS solution via the tube）, model group, topical 5-ASA group, oral Etiasa group（a release agent of mesalazine used as positive control） and oral 5-ASA group（n=12 each）. Different treatments were administered 1 day after UC induction. The normal saline（2 mL） was instilled twice a day through the tube in the sham operation group and model group. 5-ASA was given via the tube in the topical 5-ASA group（7.5 g/L, twice per day, 100 mg/kg）, and rats in the oral Etiasa group and oral 5-ASA group intragastrically received Etiasa（7.5 g/L, twice per day, 100 mg/kg） and 5-ASA（7.5 g/L, twice per day, 100 mg/kg）, respectively. The body weight was recorded every day. After 7 days of treatment, blood samples were drawn from the heart to harvest the sera. Colonic tissues were separated and prepared for pathological and related molecular biological examinations. The concentrations of 5-ASA were detected at different time points in the colonic tissues, feces and sera in different groups by using the high pressure liquid chromatography（HPLC）. The results showed that the symptoms of acute UC, including bloody diarrhea and weight loss, were significantly improved in topical 5-ASA-treated rats. The colonic mucosal damage, both macroscopical and histological, was significantly relieved and the myeloperoxidase activity was markedly decreased in rats topically treated with 5-ASA compared with those treated with oral 5-ASA or Etiasa. The mRNA and protein expression of IL-1β, IL-6, and TNF-α was down-regulated in the colonic tissue of rats topically treated with 5-ASA, significantly lower than those from rats treated with oral 5-ASA or Etiasa. The concentrations of 5-ASA in the colonic tissue were significantly higher in the topical 5-ASA group than in the oral 5-ASA and oral Etiasa groups. It was concluded that the topical administration of 5-ASA can effectively increase the concentration of 5-ASA in the colonic tissue, decrease the expression of proinflammatory cytokines, alleviate the colonic pathological damage and improve the symptoms of TNBS-induced acute UC in rats.

柱前衍生化RP-HPLC测定5-氨基水杨酸壳聚糖胶囊中5-ASA的含量

目的 采用RP -HPLC测定 5 -氨基水杨酸 (5 -ASA)壳聚糖胶囊的含量。方法 衍生化使样品中 5 -ASA乙酰化 ,色谱柱为Nucleosil1 0 0 - 5C1 8,流动相为磷酸盐缓冲液 -乙腈 -四氢呋喃 (85∶1 0∶5 ) ,流速 0 .9ml·min-1 ,检测波长 2 5 4nm。结果 5 -ASA在 0 .78～ 5 0 μg·ml-1 范围内线性关系良好 (r=0 .9993) ,RSD =1 .2 6 % (n =5 )。结论 所用方法可测定 5

Treatment of active ulcerative colitis with Yinmei Kuijie decoction combined with 5-aminosalicylic acid:A non-randomized multicenter prospective observational protocol based on real-world conditions

Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Methods:This multicenter,prospective,non-randomized,observational study will be conducted in real-world settings.A total of 204 eligible patients will be consecutively enrolled in the study.Patients in the combination treatment group will receive Yinmei Kuijie decoction in combination with 5-ASA,whereas those in the control group will be treated with 5-ASA alone.The primary endpoint will be a clinical response at week 12,defined as a≥3 point and≥30%reduction from baseline in the Mayo total score with≥1 reduction in rectal bleeding or rectal bleeding score=0 or 1.Secondary efficacy endpoints at week 12 will include health-related quality of life,mucosal healing,and inflammation indicators.Conclusion:The results of this study may provide evidence of the efficacy and safety of Yinmei Kuijie decoction combined with 5-ASA in treating patients with mildly to moderately active UC under real-world principles.The results will provide a basis for further confirmatory studies on the efficacy of Yinmei Kuijie decoction.

5-ASA colonic mucosal concentrations resulting from different pharmaceutical formulations in ulcerative colitis

AIM:To compare the mucosal concentrations of 5-aminosalicylic acid(5-ASA)resulting from different pharmaceutical formulations and analyse the influence of inflammation on the mucosal concentrations.METHODS:The study included 130 inflammatory bowel disease(IBD)patients receiving 5-ASA as pH-dependent-release formulations(73 patients),time-dependent-release formulations(11 patients),or pro-drugs(18patients).In addition,28 patients were receiving topical treatment(2-4 g/d)with pH-dependent-release formulations.Endoscopic biopsies were obtained from the sigmoid region during the colonoscopy.The 5-ASA concentrations(ng/mg)were measured in tissue homogenatesusing high-pressure liquid chromatography with electrochemical detection.The t test and Mann-Whitney test,when appropriate,were used for statistical analysis.RESULTS:Patients receiving pH-dependent-release formulations showed significantly higher mucosal concentrations of 5-ASA(51.75±5.72 ng/mg)compared with patients receiving pro-drugs(33.35±5.78 ng/mg,P=0.01)or time-dependent-release formulations(38.24±5.53 ng/mg,P=0.04).Patients with endoscopic remission had significantly higher mucosal concentrations of5-ASA than patients with active disease(60.14±7.95ng/mg vs 35.66±5.68 ng/mg,P=0.02).Similar results were obtained when we compared patients with the histological appearance of remission and patients with active histological inflammation(67.53±9.22 ng/mg vs 35.53±5.63 ng/mg,P<0.001).Significantly higher mucosal concentrations of 5-ASA were detected in patients treated with both oral and topical treatments in combination compared with patients who received oral treatment with pH-dependent-release formulations alone(72.33±11.23 ng/mg vs 51.75±5.72 ng/mg,P=0.03).CONCLUSION:IBD patients showed significant variability in mucosal 5-ASA concentrations depending on the type of formulation,and the highest mean concentration was achieved using pH-dependent-release formulations.

Colon-specific prodrugs of 4-aminosalicylic acid for inflammatory bowel disease

Despite the advent of biological products, such as anti-tumor necrosis factor-&#x003b1; monoclonal antibodies (infliximab and adalimumab), for treatment of moderate to severe cases of inflammatory bowel disease (IBD), most patients depend upon aminosalicylates as the conventional treatment option. In recent years, the increased knowledge of complex pathophysiological processes underlying IBD has resulted in development of a number of newer pharmaceutical agents like low-molecular-weight heparin, omega-3 fatty acids, probiotics and innovative formulations such as high-dose, once-daily multi-matrix mesalamine, which are designed to minimize the inflammatory process through inhibition of different targets. Optimization of delivery of existing drugs to the colon using the prodrug approach is another attractive alternative that has been utilized and commercialized for 5-aminosalicylic acid (ASA) in the form of sulfasalazine, balsalazide, olsalazine and ipsalazine, but rarely for its positional isomer 4-ASA - a well-established antitubercular drug that is twice as potent as 5-ASA against IBD, and more specifically, ulcerative colitis. The present review focuses on the complete profile of 4-ASA and its advantages over 5-ASA and colon-targeting prodrugs reported so far for the management of IBD. The review also emphasizes the need for reappraisal of this promising but unexplored entity as a potential treatment option for IBD.

5-ASA in ulcerative colitis:Improving treatment compliance

5-aminosalicylic acid(5-ASA)compounds are a highly effective treatment for ulcerative colitis(UC).While UC patient compliance in clinical studies is over 90%, only 40%of patients in every day life take their prescribed therapy.Adherence to medication has been emphasized recently by a Cochrane meta-analysis that has suggested that future trials of 5-ASA in UC should look at patient compliance rather than drug efficacy. Better compliance can be obtained by reducing the number of tablets and times of administration.Given that the 5-ASA formulations have different delivery systems that split the active moiety in various regions of the intestine,it is particularly important that an adequate dose of the drug arrives at the inflamed part of the colon.5-ASA Multi matrix(MMx)is a novel,high strength(1.2 g),oral formulation designed for oncedaily dosing.It releases the active moiety throughout the colon.Different studies with this compound have shown that it is as effective as 5-ASA enema in the treatment of mild-to-moderate,left-sided UC,and is comparable to a pH-dependent,delayed release 5-ASA (Asacol ),even if given once daily.Recently,the effectiveness in the acute phase of UC has been confirmed also in maintenance.In conclusion,at present,5-ASA MMx seems theoretically the best agent for maintaining patient compliance,and consequently,treatment effectiveness.

外源5-氨基乙酰丙酸(ALA)对低温胁迫下枇杷叶片AsA-GSH循环的影响

采用不同质量浓度(100、150、175 mg·L^(-1))的5氨基乙酰丙酸(ALA)处理低温胁迫下3年生的早钟6号枇杷容器苗,以喷施清水为对照(CK),在-3℃下低温胁迫处理3 h,比较分析不同处理对枇杷叶片过氧化氢(H_(2)O_(2))、抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量及脱氢抗坏血酸还原酶(DHAR)、谷胱甘肽还原酶(GR)、单脱氢抗坏血酸还原酶(MDHAR)和抗坏血酸过氧化物酶(APX)活性的影响。结果表明:与CK相比,外源ALA处理的枇杷叶片显著促进了叶片中抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量的增加及脱氢抗坏血酸还原酶(DHAR)、单脱氢抗坏血酸还原酶(MDHAR)、谷胱甘肽还原酶(GR)和抗坏血酸过氧化物酶(APX)活性的上升,降低过氧化氢(H_(2)O_(2))含量。说明外源ALA处理促进了低温胁迫下枇杷叶片AsA-GSH的有效循环,增强细胞的抗氧化性,提高枇杷幼苗的耐寒性。说明适当外源5氨基乙酰丙酸(ALA)处理能够调控枇杷叶片中AsAGSH循环,进而提高枇杷叶片的抗寒性,减轻枇杷在低温胁迫下的损伤,其中以175 mg·L^(-1)ALA处理效果最显著。

柱前衍生化高效液相色谱法测定美沙拉嗪肠溶片中5-ASA的含量

采用RP-HPLC测定美沙拉嗪肠溶片中5-氨基水杨酸（5-ASA）的含量。柱前衍生化使样品中5-ASA乙酰化,采用反相高效液相色谱法,色谱柱为ODS C18,流动相为磷酸盐缓冲液-乙腈（92∶8）,流速为0.9 m L·min-1,检测波长为304 nm。结果表明,5-ASA在3.12~50.0μg·m L-1范围内线性关系良好（r=0.999 6）,平均回收率为100.8%,RSD为1.27%,柱前衍生化高效液相色谱法测定美沙拉嗪肠溶片中5-ASA的含量简便、快速、准确、专属性强,适用于美沙拉嗪肠溶片中5-ASA的含量测定。

反相高效液相色谱法测定5-氨基水杨酸相关物质、原料含量及缓释片含量

目的：应用高效液相色谱法测定5-氨基水杨酸原料药及缓释片的含量。方法：反相高效液相色谱法,选择Kromasil C18柱,以甲醇-磷酸盐缓冲液(35∶65)为流动相,流速1 ml·min^(-1),检测波长254 nm。结果：浓度与峰高的回归方程为Y=395.36+17.308X,相关系数r=0.9994,线性范围83.71～837.12 μg·ml-1,精密度RSD≤1.34%,辅料对制剂的含量测定无干扰,平均回收率99.25%,RSD=0.65%。结论：测定方法简便、准确、灵敏度高。

5-氨基水杨酸对炎症性肠病相关性结肠癌和上皮内瘤变化学预防:Meta分析

目的探讨5-氨基水杨酸(5-ASA)对炎症性肠病(IBD)相关性结肠癌(IBDACa)和上皮内瘤变(IBDADys)发生率的影响,评估5-ASA对IBDACa/Dys的化学预防作用。方法检索正式发表的关于5-ASA对IBDACa/Dys化学预防的临床研究。外文数据库包括PubMed(Medline)、EMCC、OVID、the Cochrane Library;中文数据库包括万方、维普、CNKI、谷歌学术搜索。将符合要求的文献利用统计软件RevMan统计OR值和95%CI。对研究设计类型、IBD类型进行亚组分析。结果共纳入14篇文献,其中10篇为病例对照研究,4篇为队列研究。结果显示:与未使用5-ASA相比,使用5-ASA患者的IBDACa和IBDADys发生率为50%,OR=0.50(95%CI:0.34～0.73),其中病例对照研究Meta分析结果示OR=0.30(95%CI:0.10～0.92),队列研究示OR=0.56(95%CI:0.37～0.85);使用5-ASA的溃疡性结肠炎(UC)患者发生UCCa/Dys的OR=0.45(95%CI:0.27～0.77),使用5-ASA的克罗恩病(CD)患者发生CDCa/Dys的OR=0.39(95%CI:0.16～0.97)。结论 5-ASA对IBDACa/Dys有化学预防作用。

5-氨基水杨酸与乙基纤维素溶混性的计算机模拟(英文)

使用计算机辅助分子建模（CAMM）、分子力学和蒙特卡罗方法，模拟了5 -氨基水杨酸(5-ASA，C7H7NO3，美沙拉灵(sp-57-6))与乙基纤维素(EC)的溶混性 。模拟结果显示，在273K至316K的温度范围内，5-氨基水杨酸与乙基纤维素能以任何比例 混溶。得出Emix(T)=A+BT+C/T模型，A=0.3694E+04, B=-0.2610E-02,and C= 0.1818E+04, 以及Emix(T)模型标准方差，S=0.2654E-03kcal/mol。对乙基 纤维素及5-氨基水杨酸与乙基纤维素混溶过程的能量和构象分析表明，混溶过程中有乙基 纤维素分子内和乙基纤维素与乙基纤维素分子间氢键形成。对两相混溶体系进行了热力学分 析。